The immediate goal of this project is to develop methods studying the biochemistry of mitosis and cell division based on the isolation and characterization of temperature-sensitive mitotic mutants in a sample eukaryote, Aspergillus nidulans. The objective is to describe nuclear division, chromosome condensation and the mitotic spindle in biochemical terms by identifying and purifying the macromolecules and co-factors involved and by reconstructing in isolated nuclei in vitro in as many of the component systems of mitosis as possible.